Experimental Investigation of an Aspirated Fan Stage

Abstract

This paper addresses the use of viscous flow control by suction to improve compressor stage performance. The pressure ratio can be significantly increased by controlling the development of the airfoil and endwall boundary layers. This concept has been validated through an aspirated fan stage experiment performed in the MIT Blowdown Compressor Facility. The fan stage was designed to produce a pressure ratio of 1.6 at a throughflow adiabatic efficiency of 89% at a corrected rotor tip speed of 750 ft/s (229 m/s). Aspiration was applied to the airfoil surface of both the rotor and stator at a design suction rate of 0.5% of the inlet flow. Aspiration was also used on the endwall boundary layers. The measured performance of the stage agrees well with the design intent and predicted performance. An incompressible, vortex shedding model calibrated to the experimental data shows that the vortex shedding induces radial flows that redistribute flow properties in the spanwise direction.